I have the org wide setting on Activity Timeline and have verified the user setting is Activity Timeline. I've added the actions to the original page layout but the activity icons are not showing up on the record. I'm out of ideas. I've attached screen shots of an object record they do show up on and an object record they do not show up on. The page setting for both objects is the same.
In case anyone facing this problem lands up here and still wondering why Activity icons are not appearing in Activity Timeline for Case object, is because "The Case object is centered around the feed, so all mobile and lightning actions that would normally appear on the Activities Component (such as: Log a Call, Email, New Task, New Event) instead appear on the Chatter Feed Component when working with Cases in lightning."
Reference : https://help.salesforce.com/s/articleView?id=000384646&type=1
